Diagnosis of Gynecological Neoplasms by Detecting the Levels of Oviduct-Specific Glycoprotein

ABSTRACT

The present invention provides a method for detecting cancer in a patient. A sample from the patient is provided, and the level of oviduct-specific glycoprotein (OGP) in the sample is determined and compared to a control sample. Increased levels of OGP in the sample as compared to the control indicates that the patient has cancer. In one aspect, the cancer is a gynecological cancer, such as ovarian cancer. Kits for conducting the methods of the invention are also provided.

This application is a continuation of U.S. application Ser. No.10/548,580 filed Jul. 17, 2006 (now U.S. Pat. No. 7,407,762), which is anational phase entry application of PCT application no.PCT/CA2006/000367 filed Mar. 11, 2004 (which designated the UnitedStates), which claims the benefit of U.S. Provisional Patent ApplicationNo. 60/453,207 filed Mar. 11, 2003 (now abandoned). All of the priorapplications are incorporated herein in their entirety.

FIELD OF THE INVENTION

The invention relates to methods for detecting gynecological neoplasms.The method involves detecting levels of oviduct-specific glycoprotein(OGP).

BACKGROUND OF THE INVENTION

In developed countries, epithelial ovarian carcinoma (EOC) remains themost lethal gynecologic malignancy and the fourth or fifth most commoncause of death from all cancers in women. To date, however, there are nomeans for early detection of ovarian cancer, nor is there a definitivesystem for accurately determining the classification of these tumors.The fatality of this disease stems from the frequent lack of symptomsuntil the tumors have disseminated beyond the ovary. As a result, thefive-year survival rate of women with ovarian cancer remains a low anddiscouraging 40-50% [American Cancer Society, 2003; Jemal, A. et al.,2003]. If the tumor is still confined to the ovary, the chances ofsurvival increase to a substantial 80-90%. Despite the clinicalimportance of EOC, the early progression of the disease is still poorlyunderstood.

Over 85% of ovarian neoplasms, including carcinomas, cystadenomas andborderline tumors are thought to arise from the ovarian surfaceepithelium (OSE) or its derivatives, epithelial crypts and inclusioncysts [Scully, R E, 2000; Auersperg, N. et al., 2001]. The OSE is asimple mesothelium covering the ovary. As OSE progresses to malignancy,it acquires characteristics of the more complex Mullerian duct-derivedepithelia of the oviduct, endometrium, or endocervix [Scully, R. E. etal., 1998]. Like these epithelia, differentiated ovarian carcinomas formglandular and papillary structures and acquire more highly specializedand complex epithelial characteristics, including E-cadherin[Maines-Bandiera, S. L. and Auersperg, N., 1997; Sundfeldt, K. et al.,1997; Davies, B. R. et al., 1998] and CA-125 [Bast, R. C. Jr. et al.,1998]. Thus, in contrast to other tissues where carcinogenesis isaccompanied by a loss in differentiation, malignant OSE acquires a morehighly differentiated epithelial phenotype, along the lines of Mullerianduct derivatives. These changes may reflect the common embryonic originfrom which the OSE and Mullerian duct epithelia are derived, theurogenital coelomic epithelium [Scully, R. E., 2000].

Mullerian differentiation is so frequent in ovarian neoplasms that itserves as the basis for the classification of these tumors [AmericanCancer Society, 2003]. The most common type of ovarian cancer are theserous carcinomas which resemble oviductal epithelium. Except for CA125,there are at present no molecular markers that characterize tubaldifferentiation and serve as predictive or diagnostic markers in ovariancancer [Bast, R. C. Jr. et al., 1998; Hellstrom, I. et al., 2003;Mazurek, A. et al., 1998].

OGP, oviduct-specific glycoprotein, is a specific tubal differentiationmarker [Rapisarda, J. J. et al., 1993; Arias, E. B. et al., 1994; Lesse,H. J. et al., 2001]. OGP is normally secreted specifically andexclusively by the secretory epithelial cells of the oviduct, underestrogen dominance [Arias, E. B. et al., 1994; O'Day-Bowman, M. B. etal., 1995; Jaffe, R. C. et al., 1996]. It is more specific than CA125,which is normally also produced by the endometrium and endocervix[Kabawat, S. E. et al., 1983]. The human genome contains a single copyof the OGP gene located on chromosome 1p13 [Lapensee, L. et al., 1997].It is a heavily glycosylated protein, like CA125, with a molecularweight of 110- to 130-kDa and is believed to play a role infertilization and early embryonic development [Verhage, H. G. et al.,1988; Boice, M. L. et al., 1990; Boatman, D. E. and Magnoni, G. E.,1995; O'Day-Bowman, M. B. et al., 1996; Schmidt, A. et al., 1997].

SUMMARY OF THE INVENTION

The present inventors have determined that oviduct-specific glycoprotein(OGP) is a marker expressed during the aberrant Mullerian epithelialdifferentiation of ovarian neoplasms.

Accordingly, in one embodiment, the present invention provides a methodfor detecting cancer in a patient comprising:

-   -   (a) providing a sample from the patient;    -   (b) detecting the level of OGP in the sample; and    -   (c) comparing the level of OGP in the sample to a control        sample, wherein increased levels of OGP as compared to the        control indicates that the patient has cancer.

In another embodiment, the present invention provides a method formonitoring the progression of cancer in a patient, comprising:

-   -   (a) providing a sample from a patient;    -   (b) determining the level of OGP in the sample;    -   (c) repeating steps (a) and (b) at a later point in time and        comparing the result of step (b) with the result of step (c)        wherein a difference in the level of OGP expression is        indicative of the progression of the cancer in the patient.

Other features and advantages of the present invention will becomeapparent from the following detailed description. It should beunderstood, however, that the detailed description and the specificexamples while indicating preferred embodiments of the invention aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in relation to the drawing in which:

FIG. 1 is series of photographs of tissue sections providing animmunocytochemical demonstration of OGP. (A) Normal oviductal epitheliumis positive for OGP. (B) It is absent in normal OSE (arrow) but presentin epithelial inclusion cysts (arrowhead) which have undergone tubalmetaplasia. Note OGP staining in the lumen of the cyst. (C) OGP in aserous borderline tumor. (D) Invasive serous adenocarcinoma, OGPnegative.

DETAILED DESCRIPTION OF THE INVENTION

Immunohistochemical analysis for OGP was performed on 389 ovarian tumorsand 19 normal ovaries, as well as 433 cases representing 45 normaltissues and 51 benign and malignant tumor types from 37 differenttissues.

OGP was absent in ovarian surface epithelium (OSE) but present in 28/31epithelial inclusion cysts, 13/14 (93%) serous cystadenomas and 46/65(71%) serous borderline tumors. Of 183 serous adenocarcinomas, 26 (14%)were positive for OGP, including 5/8 (63%) grade 1, 7/41 (17%) grade 11and 14/134 (10%) grade III carcinomas. OGP was found in 7/14 (50%)borderline and 9/15 (60%) malignant mucinous ovarian tumors and in 10/39(26%) endometrioid adenocarcinomas. The localization of OGP in the lumenof glandular structures suggested that it was secreted. OGP was absentin 41/45 normal tissues and positive in oviduct and, weakly, in salivarygland, duodenum and ileum. Forty-six types of non-gynecological tumorswere negative, as were gynecological neoplasms except for 2/47 cervicaland 3/56 endometrial carcinomas.

Therefore, the inventors have determined that OGP is a new tubaldifferentiation marker, which characterizes benign and borderline serousneoplasms and may indicate early events in ovarian carcinogenesis.

Accordingly, evaluating OGP levels may be used in the prognostic anddiagnostic evaluation of cancers involving OGP, the identification ofsubjects with a predisposition to such cancers, and in the monitoring ofthe progress of patients with OGP related cancers.

In an embodiment of the invention, a method is provided for detectingcancer in a patient comprising:

-   -   (a) providing a sample from the patient;    -   (b) detecting the level of OGP in the sample; and    -   (c) comparing the level of OGP in the sample to a control        sample, wherein increased levels of OGP as compared to the        control indicates that the patient has cancer.

The term “OGP” as used herein is synonymous with oviduct-specificglycoprotein, oviductin, estrogen-dependent oviductal glycoprotein, ormucin 9 (MUC9). The term OGP includes all of the known OGP moleculesincluding those deposited in GenBank under accession number Q12889 (SEQID NO:1) or those referred to in Arias et al. (Arias E B et al., Biol.Reprod. 51, pages 685-694 (1994)) as well as any isoforms, variants,analogs, derivatives or fragments thereof that are useful in detectingcancer.

The phrase “detecting the level of OGP” includes the detection of thelevels of the OGP protein as well as detection of the levels of nucleicacid molecules encoding the OGP protein. Methods for detecting proteinsand nucleic acids are discussed in greater detail below.

The term “cancer” as used herein includes all cancers that areassociated with increased expression of OGP. In a preferred embodiment,the cancer is a gynecological cancer, including, but not limited to,tubal metaplasia, ovarian serous borderline neoplasms, serousadenocarcinomas, low-grade mucinous neoplasms and endometrial tumors. Ina specific embodiment, the gynecological cancer is an ovarian neoplasm,undergoing aberrant Mullerian epithelial differentiation.

The term “sample from a patient” as used herein means any samplecontaining cancer cells that one wishes to detect including, but notlimited to, biological fluids (including blood, serum, ascites), tissueextracts, freshly harvested cells, and lysates of cells which have beenincubated in cell cultures. In a preferred embodiment, the sample isgynecological tissue, serum or ascites.

The “patient” can be any mammal, preferably human, suspected of havingor having a cancer that is suspected to be associated with OGP. Thepatient is preferably a female mammal suspected of having or having agynecological cancer or tumor.

The term “control sample” includes any sample that can be used toestablish a base or normal level, and may include tissue samples takenfrom healthy persons or samples mimicking physiological fluid. Examplesof control samples include normal ovarian tissues and sections of normaloviduct.

The method of the invention may be used in the diagnosis and staging ofcancer, in particular gynecological cancer. The invention may also beused to monitor the progression of a cancer and to monitor whether aparticular treatment is effective or not. In particular, the method canbe used to confirm the absence or removal of all tumor tissue followingsurgery, cancer chemotherapy, and/or radiation therapy. The methods canfurther be used to monitor cancer chemotherapy and tumor reappearance.

In an embodiment, the invention contemplates a method for monitoring theprogression of cancer in a patient, comprising:

-   -   (a) providing a sample from a patient;    -   (b) determining the level of OGP expression in the sample;    -   (c) repeating steps (a) and (b) at a later point in time and        comparing the result of step (b) with the result of step (c)        wherein a difference in the level of OGP expression is        indicative of the progression of the cancer in the patient.

In particular, increased levels of OGP at the later time point mayindicate that the cancer is progressing and that the treatment (ifapplicable) is not being effective. In contrast, decreased levels of OGPat the later time point may indicate that the cancer is regressing andthat the treatment (if applicable) is effective.

In another embodiment of the invention, a method is provided fordetermining whether or not a cancer is benign in a patient comprising:

(a) providing a sample from the patient;

(b) detecting the level of OGP in the sample; and

(c) comparing the level of OGP in the sample to a control sample,

wherein increased levels of OGP as compared to the control indicatesthat the cancer is benign.

In an embodiment of the invention, a method is provided fordistinguishing between noninvasive and invasive gynecological cancers,comprising:

-   -   (a) providing a sample from a patient;    -   (b) determining the level of OGP expression in the sample; and    -   (c) comparing the level of OGP in the sample to a control        sample,        wherein increased levels of OGP in the sample from a patient as        compared to the control indicates that the cancer is        noninvasive.

In another embodiment of the invention, a method is provided fordistinguishing between early and late stage adenocarcinomas, comprising:

(a) providing a sample from a patient;

(b) detecting the level of OGP in the sample; and

(c) comparing the level of OGP in the sample to a control sample,

wherein increased levels in the sample as compared to the controlindicates that the cancer is an early stage adenocarcinoma.

In another embodiment, the invention contemplates a method fordetermining the potential risk to a patient of developing gynecologicalneoplasms, comprising:

(a) providing a sample from the patient;

(b) detecting the level of OGP in the sample; and

(c) comparing the level of OGP in the sample to a control sample,wherein increased levels of OGP as compared to the control indicatesthat the patient is at risk of developing gynecological neoplasms.

A variety of methods can be employed for the above described diagnosticand prognostic evaluation of cancers involving OGP, and theidentification of subjects with a predisposition to such disorders. Suchmethods may rely, for example, on the detection of nucleic acidmolecules encoding OGP, and fragments thereof, or the detection of theOGP protein using, for example, antibodies directed against OGP,including peptide fragments. Each of these is described below.

(a) Methods for Detecting Nucleic Acid Molecules

In one embodiment, the methods of the invention involve the detection ofnucleic acid molecules encoding OGP. Those skilled in the art canconstruct nucleotide probes for use in the detection of nucleic acidsequences encoding OGP in samples. Suitable probes include nucleic acidmolecules based on nucleic acid sequences encoding at least 5 sequentialamino acids from regions of OGP, preferably they comprise 15 to 30nucleotides. A nucleotide probe may be labeled with a detectablesubstance such as a radioactive label which provides for an adequatesignal and has sufficient half-life such as ³²P, ³H, ¹⁴C or the like.Other detectable substances which may be used include antigens that arerecognized by a specific labeled antibody, fluorescent compounds,enzymes, antibodies specific for a labeled antigen, and luminescentcompounds. An appropriate label may be selected having regard to therate of hybridization and binding of the probe to the nucleotide to bedetected and the amount of nucleotide available for hybridization.Labeled probes may be hybridized to nucleic acids on solid supports suchas nitrocellulose filters or nylon membranes as generally described inSambrook et al, 1989, Molecular Cloning, A Laboratory Manual (2nd ed.).The nucleic acid probes may be used to detect genes, preferably in humancells, that encode OGP. The nucleotide probes may also be useful in thediagnosis of disorders involving an OGP, in monitoring the progressionof such disorders, or in monitoring a therapeutic treatment. In anembodiment, the probes are used in the diagnosis of, and in monitoringthe progression of cancer, preferably gynecological cancer.

The probe may be used in hybridization techniques to detect genes thatencode OGP proteins. The technique generally involves contacting andincubating nucleic acids (e.g. recombinant DNA molecules, cloned genes)obtained from a sample from a patient or other cellular source with aprobe under conditions favorable for the specific annealing of theprobes to complementary sequences in the nucleic acids. Afterincubation, the non-annealed nucleic acids are removed, and the presenceof nucleic acids that have hybridized to the probe if any are detected.

The detection of nucleic acid molecules may involve the amplification ofspecific gene sequences using an amplification method such as polymerasechain reaction (PCR), followed by the analysis of the amplifiedmolecules using techniques known to those skilled in the art. Suitableprimers can be routinely designed by one of skill in the art.

Hybridization and amplification techniques described herein may be usedto assay qualitative and quantitative aspects of expression of genesencoding OGP. For example, RNA may be isolated from a cell type ortissue known to express a gene encoding OGP, and tested utilizing thehybridization (e.g. standard Northern analyses) or PCR techniquesreferred to herein. The techniques may be used to detect differences intranscript size which may be due to normal or abnormal alternativesplicing. The techniques may be used to detect quantitative differencesbetween levels of full length and/or alternatively splice transcriptsdetected in normal individuals relative to those individuals exhibitingsymptoms of a cancer involving an OGP protein or gene.

The primers and probes may be used in the above described methods insitu i.e. directly on tissue sections (fixed and/or frozen) of patienttissue obtained from biopsies or resections.

Accordingly, the present invention provides a method of detecting cancerin a patient comprising:

-   -   (a) providing a sample from the patient;    -   (b) extracting nucleic acid molecules comprising the OGP gene or        portion thereof from the sample;    -   (c) amplifying the extracted nucleic acid molecules using the        polymerase chain reaction;    -   (d) determining the presence of nucleic acid molecules encoding        OGP; and    -   (e) comparing the level of OGP in the sample to a control        sample, wherein increased levels of OGP as compared to the        control indicates that the patient has cancer.

(b) Methods for Detecting OGP Proteins

In another embodiment, the methods of the invention involve thedetection of the OGP protein. In one embodiment, the OGP protein isdetected using antibodies that specifically bind to OGP.

Antibodies to OGP may be prepared using techniques known in the art. Forexample, by using a peptide of OGP, polyclonal antisera or monoclonalantibodies can be made using standard methods. A mammal, (e.g., a mouse,hamster, or rabbit) can be immunized with an immunogenic form of thepeptide which elicits an antibody response in the mammal. Techniques forconferring immunogenicity on a peptide include conjugation to carriersor other techniques well known in the art. For example, the protein orpeptide can be administered in the presence of adjuvant. The progress ofimmunization can be monitored by detection of antibody titers in plasmaor serum. Standard ELISA or other immunoassay procedures can be usedwith the immunogen as antigen to assess the levels of antibodies.Following immunization, antisera can be obtained and, if desired,polyclonal antibodies isolated from the sera.

To produce monoclonal antibodies, antibody producing cells (lymphocytes)can be harvested from an immunized animal and fused with myeloma cellsby standard somatic cell fusion procedures thus immortalizing thesecells and yielding hybridoma cells. Such techniques are well known inthe art, (e.g., the hybridoma technique originally developed by Kohlerand Milstein (Nature 256, 495-497 (1975)) as well as other techniquessuch as the human B-cell hybridoma technique (Kozbor et al., Immunol.Today 4, 72 (1983)), the EBV-hybridoma technique to produce humanmonoclonal antibodies (Cole et al. Monoclonal Antibodies in CancerTherapy (1985) Allen R. Bliss, Inc., pages 77-96), and screening ofcombinatorial antibody libraries (Huse et al., Science 246, 1275(1989)). Hybridoma cells can be screened immunochemically for productionof antibodies specifically reactive with the peptide and the monoclonalantibodies can be isolated.

The term “antibody” as used herein is intended to include fragmentsthereof which also specifically react with an OGP or fragments thereof.Antibodies can be fragmented using conventional techniques and thefragments screened for utility in the same manner as described above.For example, F(ab′)2 fragments can be generated by treating antibodywith pepsin. The resulting F(ab′)2 fragment can be treated to reducedisulfide bridges to produce Fab′ fragments.

Chimeric antibody derivatives, i.e., antibody molecules that combine anon-human animal variable region and a human constant region are alsocontemplated within the scope of the invention. Chimeric antibodymolecules can include, for example, the antigen binding domain from anantibody of a mouse, rat, or other species, with human constant regions.Conventional methods may be used to make chimeric antibodies containingthe immunoglobulin variable region which recognizes the gene product ofOGP antigens of the invention (See, for example, Morrison et al., Proc.Natl. Acad. Sci. U.S.A. 81, 6851 (1985); Takeda et al., Nature 314, 452(1985), Cabilly et al., U.S. Pat. No. 4,816,567; Boss et al., U.S. Pat.No. 4,816,397; Tanaguchi et al., European Patent Publication EP171496;European Patent Publication 0173494, United Kingdom patent GB 2177096B).It is expected that chimeric antibodies would be less immunogenic in ahuman subject than the corresponding non-chimeric antibody.

Monoclonal or chimeric antibodies specifically reactive with a proteinof the invention as described herein can be further humanized byproducing human constant region chimeras, in which parts of the variableregions, particularly the conserved framework regions of theantigen-binding domain, are of human origin and only the hypervariableregions are of non-human origin. Such immunoglobulin molecules may bemade by techniques known in the art, (e.g., Teng et al., Proc. Natl.Acad. Sci. U.S.A., 80, 7308-7312 (1983); Kozbor et al., ImmunologyToday, 4, 7279 (1983); Olsson et al., Meth. Enzymol., 92, 3-16 (1982)),and PCT Publication WO92/06193 or EP 0239400). Humanized antibodies canalso be commercially produced (Scotgen Limited, 2 Holly Road,Twickenham, Middlesex, Great Britain.)

Specific antibodies, or antibody fragments, such as, but not limited to,single-chain Fv monoclonal antibodies reactive against OGP may also begenerated by screening expression libraries encoding immunoglobulingenes, or portions thereof, expressed in bacteria with peptides producedfrom the nucleic acid molecules of OGP. For example, complete Fabfragments, VH regions and FV regions can be expressed in bacteria usingphage expression libraries (See for example Ward et al., Nature 341,544-546: (1989); Huse et al., Science 246, 1275-1281 (1989); andMcCafferty et al. Nature 348, 552-554 (1990)). Alternatively, a SCID-humouse, for example the model developed by Genpharm, can be used toproduce antibodies or fragments thereof.

Antibodies specifically reactive with OGP, or derivatives, such asenzyme conjugates or labeled derivatives, may be used to detect OGP invarious samples (e.g. biological materials). They may be used asdiagnostic or prognostic reagents and they may be used to detectabnormalities in the level of protein expression, or abnormalities inthe structure, and/or temporal, tissue, cellular, or subcellularlocation of an OGP. In vitro immunoassays may also be used to assess ormonitor the efficacy of particular therapies. The antibodies of theinvention may also be used in vitro to determine the level of expressionof a gene encoding OGP in cells genetically engineered to produce an OGPprotein.

The antibodies may be used in any known immunoassays which rely on thebinding interaction between an antigenic determinant of OGP and theantibodies. Examples of such assays are radioimmunoassays, enzymeimmunoassays (e.g. ELISA), immunofluorescence, immunoprecipitation,latex agglutination, hemagglutination, and histochemical tests. Theantibodies may be used to detect and quantify OGP in a sample in orderto determine its role in cancer and to diagnose the cancer.

In particular, the antibodies of the invention may be used inimmunohistochemical analyses, for example, at the cellular andsubcellular level, to detect an OGP protein, to localize it toparticular cells and tissues, and to specific subcellular locations, andto quantitate the level of expression.

Cytochemical techniques known in the art for localizing antigens usinglight and electron microscopy may be used to detect OGP. Generally, anantibody of the invention may be labeled with a detectable substance andan OGP protein may be localised in tissues and cells based upon thepresence of the detectable substance. Examples of detectable substancesinclude, but are not limited to, the following: radioisotopes (e.g., 3H,¹⁴C, ³⁵S, 125I, 131I), fluorescent labels (e.g., FITC, rhodamine,lanthanide phosphors), luminescent labels such as luminol; enzymaticlabels (e.g., horseradish peroxidase, beta-galactosidase, luciferase,alkaline phosphatase, acetylcholinesterase), biotinyl groups (which canbe detected by marked avidin e.g., streptavidin containing a fluorescentmarker or enzymatic activity that can be detected by optical orcalorimetric methods), predetermined polypeptide epitopes recognized bya secondary reporter (e.g., leucine zipper pair sequences, binding sitesfor secondary antibodies, metal binding domains, epitope tags). In someembodiments, labels are attached via spacer arms of various lengths toreduce potential steric hindrance. Antibodies may also be coupled toelectron dense substances, such as ferritin or colloidal gold, which arereadily visualised by electron microscopy.

The antibody or sample may be immobilized on a carrier or solid supportwhich is capable of immobilizing cells, antibodies etc. For example, thecarrier or support may be nitrocellulose, or glass, polyacrylamides,gabbros, and magnetite. The support material may have any possibleconfiguration including spherical (e.g. bead), cylindrical (e.g. insidesurface of a test tube or well, or the external surface of a rod), orflat (e.g. sheet, test strip). Indirect methods may also be employed inwhich the primary antigen-antibody reaction is amplified by theintroduction of a second antibody, having specificity for the antibodyreactive against OGP protein. By way of example, if the antibody havingspecificity against OGP protein is a rabbit IgG antibody, the secondantibody may be goat anti-rabbit gamma-globulin labeled with adetectable substance as described herein.

Where a radioactive label is used as a detectable substance, OGP may belocalized by radioautography. The results of radioautography may bequantitated by determining the density of particles in theradioautographs by various optical methods, or by counting the grains.

Labeled antibodies against OGP protein may be used in locating tumortissue in patients undergoing surgery i.e. in imaging. Typically for invivo applications, antibodies are labeled with radioactive labels (e.g.iodine-123, iodine-125, iodine-131, gallium-67, technetium-99, andindium-111). Labeled antibody preparations may be administered to apatient intravenously in an appropriate carrier at a time several hoursto four days before the tissue is imaged. During this period unboundfractions are cleared from the patient and the only remaining antibodiesare those associated with tumor tissue. The presence of the isotope isdetected using a suitable gamma camera. The labeled tissue can becorrelated with known markers on the patient's body to pinpoint thelocation of the tumor for the surgeon.

Accordingly, in another embodiment the present invention provides amethod for detecting cancer in a patient comprising:

-   -   (a) providing a sample from the patient;    -   (b) contacting the sample with an antibody that binds to OGP;    -   (c) detecting the level of OGP in the sample; and    -   (d) comparing the level of OGP in the sample to a control        sample, wherein increased levels of OGP as compared to the        control indicates that the patient has cancer.

The methods of the invention described herein may also be performedusing microarrays, such as oligonucleotide arrays, cDNA arrays, genomicDNA arrays, or tissue arrays. Preferably the arrays are tissuemicroarrays.

In any of the above diagnostic methods, detection or measurement ofother cancer markers, in particular markers associated withgynecological cancer such as CA125, may be carried out.

II. Kits

The methods described herein may be performed by utilizing pre-packageddiagnostic kits comprising the necessary reagents to perform any of themethods of the invention. For example, the kits may include at least onespecific nucleic acid or antibody described herein, which may beconveniently used, e.g., in clinical settings, to screen and diagnosepatients and to screen and identify those individuals exhibiting apredisposition to developing cancer. The kits may also include nucleicacid primers for amplifying nucleic acids encoding OGP in the polymerasechain reaction. The kits can also include nucleotides, enzymes andbuffers useful in the method of the invention as well as electrophoreticmarkers such as a 200 bp ladder. The kit will also include detailedinstructions for carrying out the methods of the invention.

The following non-limiting examples are illustrative of the presentinvention:

EXAMPLES Example 1 Objective

With neoplastic progression, the precursor of epithelial ovariancancers, the ovarian surface epithelium (OSE), undergoes Mulleriandifferentiation, usually of the oviductal type. The aim of this examplewas to examine the expression of oviduct-specific glycoprotein (OGP), amarker of normal oviductal epithelium, for use as a diagnostic orprognostic marker for ovarian cancer.

In this example, the inventors tested the hypothesis that OGP may alsobe a marker expressed during the aberrant Mullerian epithelialdifferentiation of ovarian neoplasms.

Materials and Methods Tissues and Array Construction.

Archival formalin-fixed paraffin-embedded normal and tumor tissues werecollected from the Departments of Pathology of Vancouver Hospital andHealth Science Center and Stanford Medical Center. Immunohistochemicalstaining was performed on whole tissue sections (19 normal ovaries, 14benign serous cystadenomas) and tissue microarrays (ovarian tumor array,normal tissue array, and multi-tumor tissue array). The ovarian tumortissue array consisted of 3 benign mucinous cystadenomas, 89 borderline,and 283 malignant ovarian tumors. The multi-tissue and multi-tumortissue arrays consisted of 433 cases representing 45 normal tissues and51 benign and malignant tumor types from 37 different tissues. Fortissue microarrays, representative normal and tumor regions wereidentified from hematoxylin and eosin-stained sections. From eachspecimen duplicate tissue cores with a diameter of 0.6 mm were punchedand arrayed on a recipient paraffin block as described previously[Alkushi, A. et al., 2003]. The multitissue microarrays were constructedusing a Beecher Instruments Micro Tissue Arrayer. Sections of thecompleted tissue array blocks were cut at 4□m and placed on silanizedglass slides. These sections were used for immunohistochemical analysis.Sections of normal oviduct (mid- and late-proliferative phase) were usedas positive controls [Rapisarda, J. J. et al., 1993].

Immunohistochemistry.

Sections from paraffin-embedded tissues were deparaffinized, rehydratedand treated with 30% H₂O₂ for 5 min, and submitted to antigen retrievalby microwave oven treatment for 10 minutes in 10 mM citrate buffer at pH6.0. Slides were subsequently incubated in normal goat serum for 30 minfollowed by staining for human OGP using the rabbit anti-HuOGP antibody[Rapisarda, J. J. et al., 1993] at a dilution of 1:1000 overnight at 4°C. Tissues were then incubated with biotinylated anti-rabbitimmunoglobulins at 1:200 dilution (Vector Laboratories, Inc.) at roomtemperature for 1 hour followed by avidin-biotin peroxidase complexes(Vector Laboratories, Inc.) for 1 hour. Diaminobenzidine (VectorLaboratories, Inc.) was used as the chromogen, and hematoxylin (Sigma)as the nuclear counterstain.

Results

Histologic classification (WHO), grade (FIGO), and results of the OGPanalysis are given in Tables 1 and 2. The inventors' analysis included283 malignant ovarian adenocarcinomas of which 50 were positivelystained for OGP. Of these 50 tumors, 26 were serous, 9 were mucinous, 10were endometrioid, 1 was undifferentiated, and 4 were clear cellcarcinomas. No staining was observed in seromucinous, transitional cellor Krukenberg carcinomas (1 case each). No reactivity was found in 41types of normal tissues while the oviduct and the mucus-secretingepithelia of salivary gland, duodenum and ileum reacted weakly with theantibody. In a multitumor tissue array, 46 types of non-gynecologicalneoplasms were OGP negative. Among gynecological carcinomas, 2/47 (4%)cervical carcinomas and 3/56 (5%) endometrial carcinomas were positivefor OGP. Carcinomas of the vulva (0/11) were negative.

OGP was absent in normal OSE. Of the 19 ovaries examined, 7 had 31inclusion cysts. Staining for OGP was intense in the cells and lumen of22 epithelial inclusion cysts lined with metaplastic OSE, moderate in 6inclusion cysts with cuboidal OSE and absent in flat OSE from 3inclusion cysts. The majority of serous benign cystadenomas (13/14cases, 93%) and serous borderline tumors (46/65 cases, 71%) (FIG. 1)were OGP positive. Among invasive tumors, only 26 of 184 serousadenocarcinomas stained positively for OGP. These included 5/8 (63%)grade 1, 7/41 (17%) grade 2 and 14/134 (10%) grade 3 serous carcinomas.In addition, OGP was also present in borderline and low-grade mucinoustumors but absent in 3 mucinous cystadenomas. About 25% of theendometrioid borderline and malignant tumors also expressed OGP (Table1).

In most of the tumors, OGP staining was apical, sometimes with evidenceof secretion. All of the epithelial cells were positively stained forOGP in inclusion cysts and serous borderline tumors and in all but onebenign serous cystadenoma, while the percentage of positive cells in thecarcinoma tissues varied (Table 2). Intense staining was observed in thelumen of epithelial inclusion cysts and benign serous cystadenomas.Connective tissue stroma in both the normal and tumor tissues did notstain (FIG. 1).

Discussion

The tendency for ovarian surface epithelium (OSE) to undergo aberrantMullerian differentiation during tumorigenesis led the inventors toexamine in this example, the expression of a specific differentiationmarker for oviductal epithelium, oviduct-specific glycoprotein (OGP), innormal and neoplastic OSE. OGP was absent in normal OSE, present ininclusion cysts and in the majority of benign and borderline seroustumors, but absent in most invasive serous adenocarcinomas. Theexpression of OGP was almost entirely limited to ovarian neoplasms. Thisspecificity may help to distinguish ovarian tumors from thoseoriginating at other sites.

Developmentally, OSE arises from the mesodermal coelomic epithelium, asdo the Mullerian duct-derived epithelia of the oviduct, endometrium, andendocervix. However, unlike these latter complex tissues, OSE lacks manyof their differentiated epithelial markers [Auersperg, N. et al., 2001].Possibly the most important differentiation marker discovered to date isCA125, which has clinically proven to be an important diagnostic toolfor ovarian cancer [Bast, R. C. Jr. et al., 1998]. In this example, thepresent inventors have identified another protein, OGP which, likeCA125, is a highly glycosylated secreted protein [Verhage, H. G., etal., 1997]. Unlike CA125, OGP expression in Mullerian-duct derivednormal epithelia is limited to the oviduct [Arias, E. B. et al., 1994].The inventors have shown that OGP, like CA125, is absent in OSE butpresent in metaplastic OSE lining epithelial inclusion cysts which haveundergone tubal differentiation, and in the majority of benigncystadenomas and borderline tumors. However, whereas CA125 is present inthe majority of ovarian serous carcinomas [Bast, R. C. Jr. et al.,1998], the expression of OGP is rare in these neoplasms.

These results show that the highest proportion (63%) of invasive serousadenocarcinomas that express OGP are grade 1. However, since OGP is alsoexpressed in most epithelial inclusion cysts, which are believed to bethe preferential sites for the initiation of malignant transformation[Scully, R. E., 2000; Auersperg, N. et al., 2001], OGP may alsorepresent an early indicator of neoplastic events.

The proportion of benign and borderline serous epithelial tumors thatprogress to invasive neoplasms is still not defined, but may be quitelow [Scully, R. E., 2000; Scully, R. E. et al., 1998; Hu, J. et al.,2002]. Yet, benign and borderline serous tumors adopt a similarphenotype to serous adenocarcinomas in terms of tubal differentiation,suggesting that the common mechanisms which regulate differentiation inall these tumor types diverge from those responsible for the invasivephenotype.

The ectopic expression of OGP in ovarian epithelial tumors furthersupports the idea that OSE is a developmentally immature epithelium,which has retained the capacity to alter its state of differentiationunder physiological and pathological conditions [Auersperg, N. et al.,2001]. OGP is normally a secretory product of the oviduct and isbelieved to play an important role in early fertilization events withinthe oviduct via binding to the zona pellucida of oocytes and embryos[Verhage, H. G. et al., 1997; McCauley, T. C. et al., 2003;O'Day-Bowman, M. B. et al., 2002; Staros, A. L., and Killian, G. J.,1998]. The inventors observed that OGP staining was present in the lumenand surface of cysts and glandular structures of ovarian tumors,suggesting that it may also be secreted. In the oviduct, OGP likelyincreases the viscosity of the luminal fluid, which in turn wouldstabilize the microenvironment immediately surrounding the gametes andembryo, thereby preventing dispersal of essential nutrients and ions[Buhi, W. C., 2002]. OGP within the complex papillary structure of thenormal oviduct and of the serous adenocarcinomas may similarlycontribute to a microenvironment where there is an accumulation ofgrowth promoting factors. The lack of OGP in most high-grade ovarianadenocarcinomas raises the possibility that the cells have acquiredincreased autonomy, and thus no longer require OGP to facilitate theirgrowth.

The results show that OGP occurs in ovarian epithelial lesions,regardless of their potential to progress to invasive neoplasms. Only asmall number of grade 1 serous adenocarcinomas have been examined todate, however, a high proportion of these tumors express OGP, and itsconsistent presence in metaplastic inclusion cysts suggests that thismarker may be an indicator of early events in ovarian carcinogenesis.

Example 2 Overview

OGP expression was investigated in cultured OSE cells, serous borderlineovarian tumor cells and ovarian cancer cell lines via RT-PCR using acDNA probe specific for HuOGP [Arias E B et al., 1994], and Western blotanalysis using the Anti-OGP antibody [Rapisarda J J et al., 1993]. AsOGP is a secreted protein, the Anti-OGP antibody [Rapisarda J J et al.,1993] was used to assay conditioned media from cultured cells. The serumand ascites fluid from women was collected and tested for the presenceof OGP using ELISA and/or RIA.

Materials and Methods Reagents.

Anti-OGP antibody [Rapisarda J J et al., 1993] was used for detectingOGP protein in tissue sections and the OGP cDNA [Arias E B et al., 1994]was used as a probe in studying the mRNA expression of OGP.

Tissues and Array Construction.

Archival formalin-fixed paraffin-embedded normal and tumor tissues werecollected from a clinical database of cases. Representative normal andtumor regions were identified from hematoxylin and eosin-stainedsections. From each specimen duplicate tissue cores with a diameter of0.6 mm were punched and arrayed on a recipient paraffin block. Themultitissue microarrays were constructed using a Beecher InstrumentsMicro Tissue Arrayer. Sections of the completed tissue array blocks werecut at 4 mm and placed on silanized glass slides. These sections wereused for immunohistochemical analysis. Normal ovarian tissue sectionswere also examined for OGP expression. Sections of normal oviduct (mid-and late-proliferative phase) were used as positive controls.

Immunohistochemistry, Western Blot Analysis and ELISA Assay.

Sections from paraffin-embedded tissue were deparaffinized, rehydratedand treated with 30% H₂O₂ for 5 min, and submitted to antigen retrievalby microwave oven treatment for 10 minutes in 10 mM citrate buffer at pH6.0. Slides were subsequently incubated in normal goat serum for 30 minfollowed by staining using the rabbit anti-OGP antibody [Rapisarda J Jet al., 1993] at a dilution of 1:1000 overnight at 4° C. Tissues werethen incubated with biotinylated anti-rabbit immunoglobulins at 1:200dilution (Vector Laboratories, Inc.) at room temperature for 1 hourfollowed by avidin-biotin peroxidase complexes (Vector Laboratories,Inc.) for 1 hour. Diaminobenzidine (Vector Laboratories, Inc.) was usedas the chromogen and hematoxylin (Sigma) as the nuclear counterstain.Sections were then scored according to the following criteria: Intensity(0=negative, 1 to 3=positive), percentage of cells stained positively(<5%, 5 to 50%, >50%, 100%), and localization (apical, cytoplasmic,lumenal). Scoring results were simplified into either negative (score of0) or positive (score of 1 to 3) categories, and uninterpretable resultswere eliminated from further consideration. Score results from duplicatecores were consolidated into one score with positive staining alwayssuperceding a negative or uninterpretable result.

Discussion

Ovarian cancer, which is the prime cause of death from gynecologicalmalignancies in North American women, is usually diagnosed in latestages because there are no reliable means of early detection.Furthermore, the criteria that are available to define the precise stageand grade of ovarian carcinomas are limited and based mostly onhistopathology. Oviduct-specific glycoprotein (OGP) is a secretoryproduct of the normal oviduct. The inventors discovered in a series oftumors that OGP is produced by 75% of noninvasive borderline serousovarian adenocarcinomas but only by 24% of invasive serousadenocarcinomas, of which 38% were low grade, and 13% were high gradetumors. OGP was also present in low grade, but not in high grademucinous and endometrioid adenocarcinomas. See Tables 3 and 4. Thus, OGPis a promising diagnostic marker which will help to differentiatenoninvasive from invasive and early from late ovarian adenocarcinomas.These distinctions are important in prognosis and treatment planning. Inaddition, OGP is a secreted protein which will enable its detection inserum as a diagnostic and predictive marker for ovarian cancer.

TABLE 1 OGP expression in benign, borderline and malignant ovariantumors Subtype Positive/Total % Serous Benign 13/14 93 Borderline 46/6571 Malignant Grade 1 5/8 63 Grade 2  7/41 17 Grade 3  14/134 10 TotalMalignant  26/183 14 Seromucinous Borderline 3/5 60 Malignant 0/1 0Mucinous Benign 0/3 0 Borderline  7/14 50 Malignant Grade 1 6/9 67 Grade2 2/2 100 Grade 3 1/4 25 Total Malignant  9/15 60 EndometrioidBorderline 1/5 20 Malignant Grade 1  3/13 31 Grade 2  3/16 19 Grade 3 4/10 40 Total Malignant 10/39 26 Undifferentiated Malignant Grade 2 1/250 Grade 3 0/7 0 Total Malignant 1/9 11 Clear cell Malignant Grade 2 1/1100 Grade 3  3/33 9 Total Malignant  4/34 12 Transitional cell Malignant0/1 0 Krukenberg Malignant 0/1 0

TABLE 2 Characteristics of OGP immunohistochemical staining in ovariancarcinomas Positive/ Total Localization Intensity Percentage of PositiveCells/Case Subtype No. of cases % apical cytoplasmic weak strong <20%20-80% >80% Serous Grade 1 5/8  63 4/5 80 1/5 20 2/5 40 3/5 60 3/5 602/5 40 0/5 0 Grade 2 7/41 17 5/7 71 2/7 29 2/7 29 5/7 71 1/7 14 5/7 711/7 14 Grade 3 14/134 10  9/14 64  5/14 36  5/14 36  9/14 64  8/14 57 6/14 43  0/14 0 Total 26/183 14 18/26 69  8/26 31  9/26 35 17/26 6512/26 46 13/26 50  1/26 4 Mucinous Grade 1 6/9  67 4/6 67 2/6 33 1/6 175/6 83 1/6 17 2/6 33 3/6 50 Grade 2 2/2  100 2/2 100 0/2 0 0/2 0 2/2 1001/2 50 0/2 0 1/2 50 Grade 3 1/4  25 0/1 0 1/1 100 1/1 100 0/1 0 0/1 00/1 0 1/1 100 Total 9/15 60 6/9 67 3/9 33 2/9 22 7/9 78 2/9 22 2/9 224/9 56 Endometrioid Grade 1 3/13 31 3/3 100 0/3 0 0/3 0 3/3 100 3/3 1000/3 0 0/3 0 Grade 2 3/16 19 2/3 67 1/3 33 2/3 67 1/3 33 1/3 33 1/3 331/3 33 Grade 3 4/10 40 0/4 0 4/4 100 4/4 100 0/4 0 0/4 0 0/4 0 4/4 100Total 10/39  26  5/10 50  5/10 50  5/10 50  5/10 50  4/10 40  1/10 10 5/10 50

TABLE 3 Comparison of HuOGP expression in epithelial ovarian cancersSubtype n (%) SBLT 9/12 (75%) IMBLT 1/1 (100%) Serous carcinoma 12/51(24%) Endometrioid carcinoma 3/9 (33%) Mucinous carcinoma 4/6 (67%)Undifferentiated carcinoma 1/7 (14%)

TABLE 4 HuOGP staining classified according to architecture and grade ofepithelial ovarian cancer Architecture n (%) Subtype Glandular PapillaryUndifferentiated Total Serous carcinoma 5/13 (38%) 7/37 (19%) 12/50(24%) Grade 1 2/3 (67%) 2/3 (67%) Grade 2 3/7 (43%) 2/10 (20%) 5/17(29%) Grade 3 0/3 (0%) 4/27 (15%) 4/30 (13%) Endometrioid carcinoma 1/6(17%) 1/1 (100%) 1/2 (50%) 3/9 (33%) Grade 1 1/5 (20%) 1/1 (100%) 2/6(33%) Grade 2 1/1 (100%) 1/1 (100%) 2/2 (100%) Grade 3 0/1 (0%) 0/1 (0%)Mucinous 4/6 (67%) 4/6 (67%) Grade 1 3/5 (60%) 3/5 (60%) Grade 2 1/1(100%) 1/1 (100%) Grade 3 Undifferentiated 1/7 (14%) 1/7 (14%) Grade 1Grade 2 1/2 (50%) 1/2 (50%) Grade 3 0/5 (0%) 0/5 (0%) Total 5/12 (42%)6/14 (43%) 9/46 (20%) 20/71 (28%)

FULL CITATIONS FOR REFERENCES REFERRED TO IN THE SPECIFICATION

-   Alkushi A, Irving J, Hsu F, Dupuis B, Liu C L, Rijn M, Gilks C B.    Immunoprofile of cervical and endometrial adenocarcinomas using a    tissue microarray. Virchows Arch 2003; 442:271-7.-   American Cancer Society. Cancer facts and figures 2003. Atlanta,    American Cancer Society Inc., 2003.-   Arias E B, Verhage H G, Jaffe R C. Complementary deoxyribonucleic    acid cloning and molecular characterization of an estrogen-dependent    human oviductal glycoprotein. Biol Reprod 1994; 51:685-94.-   Auersperg N, Wong A S, Choi K C, Kang S K, Leung P C. Ovarian    surface epithelium: biology, endocrinology, and pathology. Endocr    Rev 2001;

22:255-88.

-   Bast R C Jr, Xu F J, Yu Y H, Barnhill S, Zhang Z, Mills G B. CA 125:    the past and the future. Int J Biol Markers 1998; 13:179-87.-   Boatman D E, Magnoni G E: Identification of a sperm penetration    factor in the oviduct of the golden hamster. Biol Reprod 1995;    52:199-207.-   Boice M L, McCarthy T J, Mavrogianis P A, Fazlebas A T, Verhage H G.    Localization of oviductal glycoproteins within the zona pellucida    and perivitelline space of ovulated ova and early embryos in baboons    (Papio anubis). Biol Reprod 1990; 43:340-6.-   Buhi W C. Characterization and biological roles of oviduct-specific,    oestrogen-dependent glycoprotein. Reproduction 2002; 123: 355-362.-   Davies B R, Worsley S D, Ponder B A. Expression of E-cadherin,    alpha-catenin and beta-catenin in normal ovarian surface epithelium    and epithelial ovarian cancers. Histopathology 1998; 32:69-80.-   Hellstrom I, Raycraft J, Hayden-Ledbetter M, Ledbetter J A, Schummer    M, Mcintosh M, Drescher C, Urban N, Hellstrom K E. The HE4 (WFDC2)    protein is a biomarker for ovarian carcinoma. Cancer Res 2003;    63:3695-3700.-   Hu J, Khanna V, Jones M M W, Surti U. Genomic imbalances in ovarian    borderline serous and mucinous tumors. Cancer Genet Cytogenet 2002;

139:13-23.

-   Jaffe R C, Arias E B, O'Day-Bowman M B, Donnelly K M, Mavrogianis P    A, Verhage H G. Regional distribution and hormonal control of    estrogen-dependent oviduct-specific glycoprotein messenger    ribonucleic acid in the baboon (Papio anubis). Biol Reprod 1996;    55:421-6.-   Jemal A, Murray T, Samuels A, Ghafoor A, Ward E, Thun M J. Cancer    statistics, 2003. CA Cancer J Clin 2003; 53:5-26.-   Kabawat S E, Bast R C Jr, Bhan A K, Welch W R, Knapp R C, Colvin    R B. Tissue distribution of a coelomic-epithelium-related antigen    recognized by the monoclonal antibody OC125. Int J Gynecol Pathol    1983; 2:275-85.-   Lapensee L, Paquette Y, Bleau G. Allelic polymorphism and    chromosomal localization of the human oviductin gene (MUC9). Fertil    Steril 1997; 68:702-8.-   Leese H J, Tay J I, Reischl J, Downing S J. Formation of Fallopian    tubal fluid: role of a neglected epithelium. Reproduction 2001;    121:339-46.-   Maines-Bandiera S L, Auersperg N. Increased E-cadherin expression in    ovarian surface epithelium: an early step in metaplasia and    dysplasia? Int J Gynecol Pathol 1997; 16:250-5.-   Mazurek A, Niklinski J, Laudanski T, Pluygers E. Clinical tumor    markers in ovarian cancer. Eur J Cancer Prev 1998; 7:23-35.-   McCauley T C, Buhi W C, Wu G M, Mao J, Caamano J N, Didion B A, Day    B N. Oviduct-specific glycoprotein modulates sperm-zona binding and    improves efficiency of porcine fertilization in vitro. Biol Reprod    2003; 69:828-834.-   O'Day-Bowman M B, Mavrogianis P A, Fazleabas A T, Verhage H G. A    human oviduct-specific glycoprotein: synthesis, secretion, and    localization during the menstrual cycle. Microsc Res Tech 1995;    32:57-69.-   O'Day-Bowman M B, Mavrogianis P A, Reuter L M, Johnson D E,    Fazleabas A T, Verhage H G. Association of oviduct-specific    glycoproteins with human and baboon (Papio anubis) ovarian oocytes    and enhancement of human sperm binding to human hemizonae following    in vitro incubation. Biol Reprod 1996; 54:60-9.-   O'Day-Bowman M B, Mavrogianis P A, Minshall R D, Verhage H G. In    vivo versus in vitro oviductal glycoprotein (OGP) association with    the zona pellucida (ZP) in the hamster and baboon. Mol Reprod Dev    2002; 62:248-256.-   Rapisarda J J, Mavrogianis P A, O'Day-Bowman M B, Fazleabas A T,    Verhage H G. Immunological characterization and immunocytochemical    localization of an oviduct-specific glycoprotein in the human. J    Clin Endocrinol Metab 1993; 76:1483-8.-   Schmidt A, Mavrogianis P A, O'Day-Bowman M B, Jaffe R C, Verhage    H G. Characterization of antibodies generated against a conserved    portion of oviductal glycoprotein (OGP) and endogenous hamster OGP    and their ability to decrease sperm binding to the zona pellucida in    vitro. Am J Reprod Immunol 1997; 38:377-83.-   Scully R E, Young R H, Clement P B. Atlas of tumor pathology, third    series, fascicle 23. Tumors of the ovary, maldeveloped gonads,    fallopian tube and broad ligament. Washington D.C.: Armed Forces    Institute of Pathology; 1998.-   Scully R E. Influence of origin of ovarian cancer on efficacy of    screening. Lancet 2000; 355:1028-1029.-   Staros A L, Killian G J. In vitro association of six oviductal fluid    proteins with the bovine zona pellucida. J Reprod Fertil 1998;    112:131-7.-   Sundfeldt K, Piontkewitz Y, lvarsson K, Nilsson O, Hellberg P,    Brannstrom M, Janson P O, Enerback S, Hedin L. E-cadherin expression    in human epithelial ovarian cancer and normal ovary. Int J Cancer    1997; 74:275-80.-   Verhage H G, Fazleabas A T, Mavrogianis P A, O'Day-Bowman M B,    Schmidt A, Arias E B, Jaffe R C. Characteristics of an oviductal    glycoprotein and its potential role in fertility control. J Reprod    Fertil Suppl 1997; 51:217-26.-   Verhage H G, Fazleabas A T, Donnelly K. The in vitro synthesis and    release of proteins by the human oviduct. Endocrinology 1988;    122:1639-45.-   Verhage H G, Mavrogianis P A, O'Day-Bowman M B, Schmidt A, Arias E    B, Donnelly K M, Boomsma R A, Thibodeaux J K, Fazleabas A T, Jaffe    R C. Characteristics of an oviductal glycoprotein and its potential    role in the fertilization process. Biol Reprod 1998; 58:1098-101.

1. A method of detecting cancer in a patient comprising: (a) providing asample from the patient; (b) determining the level of oviduct specificglycoprotein (OGP) in the sample; and (c) comparing the level of OGP inthe sample to a control sample, wherein increased levels of OGP ascompared to the control indicates that the patient has cancer.
 2. Amethod according to claim 1 for monitoring the progression of cancer ina patient comprising: (a) providing a sample from a patient; (b)determining the level of OGP in the sample; (c) repeating steps (a) and(b) at a later point in time and comparing the result of step (b) withthe result of step (c) wherein a difference in the level of OGP isindicative of the progression of the cancer in the patient.
 3. A methodaccording to claim 1 for determining whether or not a cancer is benignin a patient comprising: (a) providing a sample from the patient; (b)detecting the level of OGP in the sample; and (c) comparing the level ofOGP in the sample to a control sample, wherein increased levels of OGPas compared to the control indicates that the cancer is benign.
 4. Amethod according to claim 1 for distinguishing between noninvasive andinvasive cancers, comprising: (a) providing a sample from a patient; (b)determining the level of OGP expression in the sample; and (c) comparingthe level of OGP in the sample to a control sample, wherein increasedlevels of OGP in the sample from a patient as compared to the controlindicates that the cancer is noninvasive.
 5. A method according to claim1 wherein the cancer is gynecological cancer.
 6. A method according toclaim 5 wherein the cancer is ovarian cancer.
 7. A method according toclaim 6 wherein the cancer is early stage ovarian adenocarcinoma.
 8. Amethod according to claim 5 wherein the cancer is an ovarian neoplasm.9. A method according to claim 8 wherein the ovarian neoplasm isundergoing Mullerian epithelial differentiation.
 10. A method accordingto claim 1 wherein the level of nucleic acid molecules encoding OGP aredetermined in step (b).
 11. A method according to claim 10 wherein thelevel of expression of OGP mRNA is determined.
 12. A method according toclaim 1 wherein the level of the OGP protein is determined in step (b).13. A method according to claim 12 wherein an antibody is used todetermine the levels of the OGP protein.
 14. A method according to claim1 wherein the sample is gynecological tissue, serum or ascites.
 15. Akit for detecting cancer in a patient comprising (i) reagents forconducting a method according to claim 1 and (ii) instructions for itsuse.
 16. A kit according to claim 15 wherein the reagents comprisenucleic acid primers for amplifying mRNA coding for OGP in a reversetranscriptase polymerase chain reaction.
 17. A kit according to claim 15wherein the reagents comprise antibodies specific to the OGP protein.18. A kit for monitoring the progression of cancer in a patientcomprising (i) reagents for conducting a method according to claim 2 and(ii) instructions for its use.
 19. A kit according to claim 18 whereinthe reagents comprise nucleic acid primers for amplifying mRNA codingfor OGP in a reverse transcriptase polymerase chain reaction.
 20. A kitaccording to claim 18 wherein the reagents comprise antibodies specificto OGP protein.
 21. A kit for determining whether or not a cancer isbenign in a patient comprising (i) reagents for conducting a methodaccording to claim 3 and (ii) instructions for its use.
 22. A kitaccording to claim 21 wherein the reagents comprise nucleic acid primersfor amplifying mRNA coding for OGP in a reverse transcriptase polymerasechain reaction.
 23. A kit according to claim 21 wherein the reagentscomprise antibodies specific to OGP protein.
 24. A kit fordistinguishing between noninvasive and invasive cancers comprising (i)reagents for conducting a method according to claim 4 and (ii)instructions for its use.
 25. A kit according to claim 24 wherein thereagents comprise nucleic acid primers for amplifying mRNA coding forOGP in a reverse transcriptase polymerase chain reaction.
 26. A kitaccording to claim 24 wherein the reagents comprise antibodies specificto OGP protein.